There is known a very large number of baking and other food additives based on undistilled or distilled monoglycerides, and for many different purposes. Thus, such additives have found a widespread use in cakes for the improvement of whipping effect and improved mixing of the ingredients whereby for instance sponge cakes may be prepared by an "all-in" procedure. The use of emulsifiers will also improve the stability of the cake batter and give a nice and homogenous cake which is more attractive for the consumer. Baking aids for cakes traditionally have been employed in the form of a paste (e.g. stirred with water) or in the form of a powder, in both cases containing normally 20 to 40% emulsifier. In order for emulsifiers to having whipping effect, it is necessary that the emulsifier is present in the .alpha.-crystalline form. Some emulsifiers in the .alpha.-crystalline form are able to stabilize a foam system consisting of protein, starch, water (or air) and sugar as for instance in cakes. This property is the reason for the good whipping effect of these emulsifiers.
In order to ensure that, e.g., monoglyceride is present in the .alpha.-crystalline form, one has combined monoglyceride with other emulsifiers with capability of stabilizing the monoglyceride in the .alpha.-crystalline form.
From i.a. U.S. Pat. Nos. 3,034,897 and 3,034,898 it is known that monoglycerides in the .alpha.-crystalline form may be stabilized to a considerable degree by causing the monoglyceride to be present in conjoined crystals together with fatty acid esters of propylene glycol. The powdery compositions thus known must be stirred thoroughly into water (be "hydrated") in order to be usable.
In DK patent specification No. 107,347 and the corresponding U.S. Pat. No. 3,479,189 there is described a storage stable baking and whipping aid in a state hydrated into the form of a paste or gel and meant especially for sweet cakes and desserts, and containing monoglyceride, propylene glycol monoester, both of fatty acids in which at most 5% of the fatty acid residues are unsaturated, and a hydrophilic co-emulsifier in a solvent mixture consisting of water and at least one organic solvent in the form of a liquid edible alcohol, a liquid edible ester thereof or aqueous sorbitol containing a crystal inhibitor. As co-emulsifier, the purpose of which is to contribute to the dispersion of the monoesters into the medium and the baking aid into the other components of the batter or dessert, there is especially used alkali metal salts of fatty acid, but also for instance lactylated or acetylated mono-diglycerides may be used for the purpose.
The preparation of such paste- or gel-formed baking aids is laborious and comparatively expensive and the keeping quality in the active .alpha.-crystal form is limited. To some degree they have therefore been replaced by powdery products, e.g. formed from the above described paste- or gel-formed mixture by emulsifying in water together with a suitable carrier substance, e.g. defatted milk dry matter or maltodextrin, and subsequent homogenization and spray drying to form a powder having a suitable fineness.
To obtain a satisfactory result with powdery baking aids it is necessary to prepare an emulsion of the emulsifier, water and carrier substance, which is thereupon spray dried. There is thereby obtained a good distribution of the emulsifiers and a large surface on the carrier substance, which is important in order to the whipping effect in the cake batter.
The preparation of such emulsifier mixtures is described in U.S. Pat. No. 2,913,342 and Swedish patent specification No. 197,856. As inactive carrier substances there is employed sucrose, casein and sodium caseinate.
The advantage of powdery products is that they are easier to use and dose correctly and uniformly than gel-formed products and that they can be used in premixed dry cake mixes and dessert mixes.
The problems mentioned in the preparation of pastes or gels and the costs of spray drying and the content of inactive carrier substances such a milk dry matter or maltodextrin, however, set a limit for the use of these products, partly for economic and partly for technological reasons.
In order for such powdery emulsifier mixtures to act as aerating agents in cake batters and whipped desserts and similar products, it is important that the powder particles can be dispersed and swell in the aqueous phase present in the product, be it a cake batter or whipped dessert, at the temperature at which the ingredients are mixed, normally 20.degree. to 25.degree. C.
The particle size of a baking or whipping aid has an important influence on the dispersibility in, e.g., batter systems. This again influences the effect thereof.
An improved dispersibility has, i.a., been obtained by the abovementioned powdery emulsifiers containing (hydrophilic) carrier substances.
A further improvement of the dispersibility has been obtained by incorporating monoglyceride containing unsaturated fatty acid residues into the emulsifier mixtures. However, such emulsifier mixtures do not give a good whipping effect and therefore are not particularly suitable for cakes of the types especially aimed at by the invention, or for whipped desserts, ice cream, toppings or icings.
Besides the already mentioned powdery mixture of monoglycerides and propylene glycol monoesters, there has recently appeared two descriptions of more efficient additives for cakes. One is CA patent specification No. 1,113,304 which describes emulsifiers for chemically leavened bakery products, consisting of 25-75% by weight of propylene glycol monoesters, 5-30% by weight of monoglycerides of saturated C.sub.8-22 fatty acids, 5-30% by weight of monoglycerides of unsaturated C.sub.8-22 fatty acids and 10-30% by weight of mono-succinylated monoglycerides of saturated C.sub.8-22 fatty acids (the latter succinylated monoglyceride thus still contains one free hydroxy group); the emulsifier is stated to be a solid solution and is prepared by mixing the components in the molten state, after which the mixture is cooled and pulverized.
The other is U.S. Pat. No. 4,310,556 which describes "food emulsifiers" consisting of a likewise solid solution in the form of a powdery mixture of about 15-40 parts by weight of succinylated monoglycerides, about 25-45 parts by weight of monoglycerides having an iodine number of about 2-15, about 15-40 parts by weight of propylene glycol monoesters and about 5-18 parts by weight of C.sub.8-22 fatty acids.
From U.S. Pat. No. 4,483,880 there is known a powdered emulsifier mixture, generally usable in starch-containing foods, consisting of 65-90% monoglycerides containing saturated fatty acid, 35-10% monoglycerides containing unsaturated fatty acid and less than 10% of one or more esters of diacetyltartaric acid, tartaric acid, acetic acid or citric acid and monoglyceride, which are mixed in the melted state after which the melt is directly spray-crystallized to form a powder, or the melt is cooled or pulverized to a powder having a suitable particle size.